Currently, for injector driver applications, in order to control the time of injection phases, either a dedicated input pin is needed for each phase, or a combination of pre-set fixed timing registers and internal timers is used. Conventional implementations do not permit use of a single input to accurately control time on more than two different phases. Approaches using a dedicated input pin (signal) could have accurate timing control on the fly. However, such approaches need additional pins for each phase transition. For example, in order to control the time for the pre-peak, boost-pull-in, and pull-in phases, three dedicated pins are needed. This means more pins in the ASIC, more control pins in the microcontroller, more board traces, and thus increased system cost. The approaches that use a combination of (a group of) pre-set fixed timing registers and internal timers could also control the time for the phases. Each phase needs at least one register to set the desired time. However, the register cannot be changed on the fly. Thus, if there is a timing change during the injection, the change is not applied in real time in the current injection pulse.
Thus, there remains a need in the art for an implementation of an interrupt control scheme into the fuel system pre-driver so that the timing for all different injection phases can be accurately controlled within the same injection cycle through only one pin in the pre-driver ASIC.